Selectable declarative requirement levels

ABSTRACT

A network is configured. Constraints are stored. A plurality of processing stages is processed. For at least one of the plurality of processing stages, an application agent utilizes an input declarative requirement with at least some of the constraints to determine an output declarative requirement that is at a lower level than a level of the input declarative requirement. Each processing stage corresponds to an interaction agent that is able to specify the input declarative requirement for that stage.

BACKGROUND OF THE INVENTION

In order to configure a network, a network administrator may specify adeclarative requirement of a desired network configuration. For example,the network administrator may specify a declarative requirement of whatthe final network configuration should be rather than the mechanics ofhow to accomplish the network configuration. Often these declarativerequirements must include very specific types of requirements. However,in many instances, the network administrator may desire flexibility inbeing able to specify different levels and types of declarativerequirements rather than the traditional single type of declarativerequirement understood by a traditional system. For example, for certainconfigurations, the network administrator may want to specify high leveldeclarative requirements while for other configuration instances, thenetwork administrator may want to specify lower and more specificdeclarative requirements. In other cases, the network administrator maywant to mix different types of desired requirements by specifyingdeclarative requirements at a high level along with specificrequirements for specific aspects of the declarative requirements.Therefore, there exists a need for a more flexible way to specifydeclarative requirements.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the invention are disclosed in the followingdetailed description and the accompanying drawings.

FIG. 1 is a diagram illustrating an embodiment of a network managementenvironment.

FIG. 2A is a flowchart illustrating an embodiment of a process forpublishing network requirements.

FIG. 2B is a flowchart illustrating an embodiment of a process forprocessing requirements.

FIG. 3A is a flowchart illustrating an embodiment of a process forpublishing device requirements.

FIG. 3B is a flowchart illustrating an embodiment of an example processfor automatically configuring a network using received declarativerequirements.

FIG. 3C is a block diagram illustrating processing stages/levels of anexample process for automatically configuring an L3 Clos network.

FIG. 4 is a flowchart illustrating an embodiment of a process forgenerating native hardware instructions.

FIG. 5 is a flowchart illustrating an embodiment of a process forverifying an expectation.

DETAILED DESCRIPTION

The invention can be implemented in numerous ways, including as aprocess; an apparatus; a system; a composition of matter; a computerprogram product embodied on a computer readable storage medium; and/or aprocessor, such as a processor configured to execute instructions storedon and/or provided by a memory coupled to the processor. In thisspecification, these implementations, or any other form that theinvention may take, may be referred to as techniques. In general, theorder of the steps of disclosed processes may be altered within thescope of the invention. Unless stated otherwise, a component such as aprocessor or a memory described as being configured to perform a taskmay be implemented as a general component that is temporarily configuredto perform the task at a given time or a specific component that ismanufactured to perform the task. As used herein, the term ‘processor’refers to one or more devices, circuits, and/or processing coresconfigured to process data, such as computer program instructions.

A detailed description of one or more embodiments of the invention isprovided below along with accompanying figures that illustrate theprinciples of the invention. The invention is described in connectionwith such embodiments, but the invention is not limited to anyembodiment. The scope of the invention is limited only by the claims andthe invention encompasses numerous alternatives, modifications andequivalents. Numerous specific details are set forth in the followingdescription in order to provide a thorough understanding of theinvention. These details are provided for the purpose of example and theinvention may be practiced according to the claims without some or allof these specific details. For the purpose of clarity, technicalmaterial that is known in the technical fields related to the inventionhas not been described in detail so that the invention is notunnecessarily obscured.

Configuring network devices is disclosed. In some embodiments,constraints are received. For example, information about networkresources and/or one or more policies that define how to determine anoutput from an input requirement are received and/or automaticallydetermined. In some embodiments, there exists a plurality of processingstages in determining device requirements. Each stage corresponds to oneor more input declarative requirements that can be specified using aninteraction agent. An application agent of each stage merges an inputdeclarative requirement with at least some of the constraints todetermine a lower level of output requirement than the level of theinput declarative requirement for that level. The lower level outputrequirement may be utilized as the input declarative requirement for asubsequent lower level processing stage.

In some embodiments, the network may be a collection of one or moredevices that are able to be connected together. In some embodiments, atleast three components work together to manage, configure, and/ormonitor a network. For example, an interaction agent interacts with auser to receive and provide desired requirements, specifications, andstatus updates; an application agent implements and manages the desiredrequirements and status updates across various network devices; and aproxy agent of each network component implements and manages devicespecific configurations and status updates of its network device. Insome embodiments, a set of network requirements is received at aninteraction agent. For example, desired requirements of a networkconfiguration are received from a user via the interaction agent. Atleast a portion of the network requirements is published to a systemdata store. For example, rather than maintaining state information andmanaging communication between agent components directly at each agentcomponent, the system data store is utilized to track and provide stateand communications of agent components. The published networkrequirements may be received at an application agent. For example, theapplication agent has subscribed to the network requirements stored inthe system data store and is notified when the set of networkrequirements is stored in the system data store. Device requirements maybe published by the application agent to the system data store for aplurality of devices. For example, the application agent has identifiedthe plurality of devices to be utilized to implement the publishednetwork requirements and has generated specific device requirements foreach of the plurality of identified devices. The applicable devicerequirements may be received at a proxy agent of a network device. Forexample, each proxy agent of each of the identified devices hassubscribed to and receives the corresponding device requirements of itsnetwork device. Native hardware instructions are generated by the proxyagent to configure an individual network device. For example, the proxyagent translates the received device requirements to generate thehardware instructions to implement the received device requirements.

FIG. 1 is a diagram illustrating an embodiment of a network managementenvironment. Management server 102 is connected to data store 104,network device 106, and network device 108 via network 110. In someembodiments, management server 102 provides a network configuration,monitoring, and management solution. For example, a user may utilize asolution at least in part provided by management server 102 to setup anetwork configuration, setup a network device, monitor performance of anetwork, monitor devices of a network, automate tasks, and otherwiseperform management of devices of the network. In the example shown,management server 102 is utilized to manage at least network device 106and network device 108. Management server 102 includes interaction agent112 and application agent 114. For example, interaction agent 112 andapplication agent 114 are software components and/or hardware componentsof management server 102. In some embodiments, management server 102 isspecialized custom hardware. In some embodiments, management server 102is utilized to configure hardware network switches.

Interaction agent 112 facilitates interaction with users to receive andprovide desired requirements, specifications, and status updates. Forexample, a user accesses interaction agent 112 via a user interface(e.g., web interface, application interface, command line interface,application programming interface (API), configuration file interface,etc.) provided directly and/or remotely (e.g., via display, wiredconnection, network, etc.). Using the user interface, a user may providehigh level requirements that specify a desired configuration of adesired network/device and/or receive information regarding status ofdevices/components of the desired network and/or an implementationstatus regarding the desired configuration requirements. Interactionagent 112 may manage a plurality of application agents. For example,interaction agent 112 selects an application agent among a plurality ofapplications to achieve/complete a desired network requirement. In someembodiments, interaction agent 112 is accessed by a user via a RESTfulAPI. For example, HTTP methods (e.g., GET, PUT, POST, DELETE, etc.) areutilized to access and manage information via the API. URI may beutilized to reference state and resources. In some embodiments, a userspecifies one or more declarative requirements of a desired networkconfiguration using interaction agent 112. The declarative requirementsmay be specified at one or more selected stages/levels among a pluralityof stages/levels. In some embodiments, a user specifies one or moreconstraints (e.g., resources, policies, etc.) of a desired networkconfiguration using interaction agent 112.

Application agent 114 implements and manages the desired networkrequirements, configurations, and status updates across various networkdevices. In some embodiments, application agent 114 provides devicerequirement instructions to and receives status information from variousdevices of a network being managed. For example, using desired networkrequirements, application agent 114 determines individual devicerequirements to implement the desired network requirements. The devicerequirements determined by application agent 114 may be declarativedevice requirements such that the device requirements may be translatedto any of a number of different native device instructions (e.g., nativeinstructions of devices of different vendors, device versions, deviceoperating systems, programming interfaces, etc.) to implement the devicerequirements. In the example shown, application agent 114 has selectednetwork devices 106 and 108 to implement the desired networkrequirements and generates unique device requirements for each networkdevice 106 and 108.

In some embodiments, in translating the desired network requirements tothe device requirements, a plurality of different successive processingstages/levels may be utilized. The network requirements may be specifiedfor any of the different processing stage levels. For example, networkrequirements may be specified at the most general and highest leveland/or at a lower and more specific stage/level. Each processingstage/level may translate an input declarative requirement to an outputdeclarative requirement that may be utilized as the input declarativerequirement for the next subsequent lower processing stage/level. Foreach processing stage/level, the application agent merges an inputdeclarative requirement with one or more constraints (e.g., resourcesavailable, policies to follow, etc.) to determine the outputrequirement. By being able to provide desired declarative networkrequirements of any selected stage/level of a plurality of differentprocessing stages/levels, a user is given the option to tune thelevel/amount of control desired by the user in configuring the network.For example, a network administrator who desires to quickly setup adefault configuration network may specify declarative requirements atthe highest stage/level while a network administrator who desires tosetup a more customized and specific network may specify declarativerequirements at a lower stage/level. In some embodiments, eachprocessing stage/level performs a different function. For example, oneprocessing stage/level determines a logical connectivity in its outputdeclarative requirements, another processing stage/level determinesphysical connectivity in its output declarative requirements, andanother processing stage/level determines a cabling in its outputdeclarative requirements.

Proxy agent 116 receives its device requirements for network device 106and proxy agent 118 receives its device requirements for network device108. Each proxy agent may generate native hardware instructionsimplementing its device requirements to configure its associatedindividual network device. In some embodiments, each proxy agent reportsinformation about a status, an operation, and/or other information ofits associated device(s). Application agent 114 may then collect andprocess the reported information to report the information and/or toperform a responsive action. For example, when a proxy agent provides astatus update that its associated device is overloaded, the applicationagent may add a new device to a network to offload processing and/or tomove a processing task of the overloaded device to another networkdevice. The collected status information may be provided by applicationagent 114 to interaction agent 112 as a report and/or a request foraction.

Communication between interaction agent 112, application agent 114, andproxy agents 116 and 118 are facilitated via data store 104. In someembodiments, interaction agent 112, application agent 114, and proxyagents 116 and 118 do not directly communicate with each other. Forexample, rather than maintaining state information and managingcommunication between agent components directly at each agent component,the data store 104 is utilized to track and provide state informationand communications of agent components. All state information (e.g.,state of device, requirements, configurations, etc.) of the agents maybe stored in data store 104 rather than storing state information in theagents. When data is to be communicated between the agents, a sendingagent publishes/stores the data to be communicated to data store 104.The agent receiving the data may read the data from data store 104and/or may be pushed the data. For example, an agent subscribes to benotified when a certain type of data is stored in data store 104 and theagent is notified when a new or a modification to the certain type ofdata is received at data store 104. In some embodiments, an agentperiodically polls/checks data store 104 for data. Data store 104 may beincluded in a networked storage service. In the example shown, theagents access data store 104 via network 110. In some embodiments, datastore 104 is directly connected to management server 102 via anon-shared connection. In various embodiments, data store 104 isincluded in any of the components shown in FIG. 1. For example, datastore 104 is included in server 102. Data store 104 may include a serverthat manages data stored in data store 104 (e.g., manages datasubscriptions). Examples of data store 104 include a database, a highlyavailable storage, a distributed storage, a cloud storage, a dataservice, or any other type of data storage.

Network device 106 and network device 108 may be any type of deviceconnected to network 110. Examples of network device 106 and networkdevice 108 include a server, a network switch, a network router, a cacheserver, a storage device, a hypervisor switch, virtual router, a loadbalancer, a firewall, a network fabric device, a virtual network device,a software device, a software component, or any type of computer ornetworking device that may be physical or virtual. Proxy agent 116 is asoftware and/or hardware component included in network device 106. Proxyagent 116 manages network device 106. Proxy agent 118 is a softwareand/or hardware component included in network device 108. Proxy agent118 manages network device 108. Examples of network 110 include one ormore of the following: a direct or indirect physical communicationconnection, a mobile communication network, Internet, intranet, LocalArea Network, Wide Area Network, Storage Area Network, and any otherform of connecting two or more systems, components, or storage devicestogether. Other communication paths may exist and the example of FIG. 1has been simplified to illustrate the example clearly.

Although single instances of many of the components shown in FIG. 1 havebeen shown to simplify the diagram, additional instances of any of thecomponents shown in FIG. 1 may exist. For example, any number ofmanagement servers, storages, and network devices may exist. Managementserver 102 may be a cluster of servers and storage 104 may be adistributed storage. Any number of interaction agents, applicationagents, and/or proxy agents may exist. A single server/device mayinclude any number of interaction agents, application agents, and/orproxy agents. A single interaction agent, application agent, and/orproxy agent may provide a service for a plurality of services/devices. Asingle interaction agent may interact with a plurality of applicationagents. For example, different types of network requirements and statusupdates may be handled by different application agents that allinterface with a single interaction agent. Although the example shown inFIG. 1 shows application agent and interaction agent included/installedon the same management server, they may be included in differentservers/devices. Although the example shown in FIG. 1 shows each proxyagent included/installed in their respective associated network device,the proxy agents may be included in different servers/devices. Forexample, the proxy agents are included in management server 102.Although the example shown in FIG. 1 shows that a single proxy agent isonly assigned to manage a single associated network device, in someembodiments, a single proxy agent may be assigned to manage a pluralityof network devices. Components not shown in FIG. 1 may also exist. Insome embodiments, each resource (e.g., each agent, server, and networkdevice) of FIG. 1 may belong to a domain. For example, resourcesbelonging to the same domain are interoperable and may function togetherto perform a network configuration and/or management task. In someembodiments, each resource may only belong to one domain and onlyresources within the same domain are guaranteed to be interoperable toperform a network configuration and/or management task. Certainresources may belong to a plurality of domains. A plurality of domainsmay be utilized to manage a single network. The components shown in FIG.1 may be components of one or more domains. Any of the components shownin FIG. 1 may be a physical or a virtual component.

FIG. 2A is a flowchart illustrating an embodiment of a process forpublishing network requirements. The process of FIG. 2A may beimplemented on management server 102 of FIG. 1. In some embodiments, theprocess of FIG. 2A is performed by interaction agent 112 of FIG. 1.

At 202, a set of network requirements is received at an interactionagent. In some embodiments, the interaction agent is an interactionagent such as interaction agent 112 of FIG. 1. The interaction agent mayinterface with a user and/or a user system. The interaction agent may bea software and/or hardware component and may be included in a serverutilized to manage a network (e.g., manage network devices). In someembodiments, the interaction agent manages one or more applicationagents. For example, the interaction agent selects one or moreapplication agents that will be implementing the set of networkrequirements and/or reporting on their status. A user or a user systemmay access the interaction agent via a user interface (e.g., webinterface, visual display interface, application interface, command lineinterface, application programming interface (API), RESTful API,configuration file interface, etc.) provided directly and/or remotely(e.g., via display, wired connection, network, etc.).

In some embodiments, the set of network requirements includes aspecification of a desired configuration, setting, topology, and/orother specifications of a network/service and/or one or more devicesconnected or able to be connected to the network. In some embodiments,the set of network requirements includes a set of declarativerequirements. For example, declarative requirements express a desiredconfiguration of network components without specifying an exact nativedevice configuration and control flow. By utilizing declarativerequirements, what should be accomplished may be specified rather thanhow it should be accomplished. Declarative requirements may becontrasted with imperative instructions that describe the exact deviceconfiguration syntax and control flow to achieve the configuration. Byutilizing declarative requirements rather than imperative instructions,a user and/or user system is relieved of the burden of determining theexact device configurations required to achieve a desired result of theuser/system. For example, it is often difficult and burdensome tospecify and manage exact imperative instructions to configure eachdevice of a network when various different types of devices fromdifferent vendors are utilized. The types and kinds of devices of thenetwork may dynamically change as new devices are added and devicefailures occur. Managing various different types of devices fromdifferent vendors with different configuration protocols, syntax, andsoftware versions to configure a cohesive network of devices is oftendifficult to achieve. Thus, by only requiring a user/system to specifydeclarative requirements that specify a desired result applicable acrossvarious different types of devices, management and configuration of thenetwork devices becomes more efficient.

In various embodiments, the set of network requirements specifies adesired configuration, a desired action, a command, or any otherinstruction or desired result of one or more devices. One example of theset of network requirements is a set of requirements to establish anetwork topology. For example, a mesh network (e.g., Layer 3 ClosNetwork) is desired to be established and the set of networkrequirements specifies desired parameters of the desired mesh network.In a Clos Network, every lower-tier switch (e.g., leaves) is connectedto each of the top-tier switches (e.g., spines) in a full-mesh topology.A portion of an example set of requirements that specify an instructionto establish an L3 Clos network configuration received via a receivedrequirements file is below:

-   -   Network topology type=Clos    -   # of spines=16    -   # of leaves=128    -   IP address pool=10.0.0.0/24        The above requirements specify that a Clos network with 16 spine        network switches and 128 leaf network switches should be        established and the switches of the Clos network should be        assigned an IP address from the range 10.0.0.1 through        10.0.0.255.

In some embodiments, the set of requirements is verified for validityand correctness. For example, it is verified that the set of networkrequirements has been received from an authorized and validated source,the provided requirement specification syntax is correct, validrequirements have been provided, all required parameters for a desiredresult have been specified, and provided requirements are able to beachieved via available hardware/software resources/devices.

In some embodiments, the set of requirements is a set of declarativerequirements that specify a desired configuration, a desired action, adesired mapping result, a command, or any other desired result of one ormore declarative requirement processing stages/levels. In someembodiments, the set of requirements may be specified for one or moreselected processing stages/levels of successive declarative requirementprocessing stages/levels. For example, there exists a plurality ofprocessing successive stages/levels that successively require morespecific/lower stage/level declarative requirements at each lowerstage/level and a user may specify declarative requirements for any oneof the stages/levels. In some embodiments, each of the processingstages/levels determines additional aspects of a network to beconfigured. For example, the output of each processing stage/levelincludes additional declarative requirements that further defineadditional aspects of the desired network.

In some embodiments, the set of declarative requirements is specifiedfor a selected processing stage/level. For example, network declarativerequirements can be specified for the most general and highestprocessing stage/level or for a lower and more specific processingstage/level based on the amount of customization and detail desired tobe controlled when automatically setting up a network defined by thespecified declarative requirements. Each processing stage/level maytranslate an input requirement to an output requirement that may beutilized as the input requirement for the next processing stage/level,if applicable. For example, by successively converting declarativerequirements to a lower stage/level declarative requirement with morespecificity at each of the plurality of processing levels/stages,declarative requirements for each specific device to be configured byeach proxy agent of each specific device are determined.

In some embodiments, rather than requiring a user to specify declarativerequirements that conform to a single specificity level, the user isable to specify declarative requirements at any of a plurality ofdifferent specificity levels corresponding to the plurality ofprocessing levels/stages. Thus, by being able to provide desired networkdeclarative requirements at any of a plurality of different selectedlevels, a user is given the option to specify the level/amount ofcontrol desired by the user in configuring the network. For example, anetwork administrator who desires to quickly setup a defaultconfiguration network may specify declarative requirements at thehighest stage/level (e.g., number of servers to be supported) while anetwork administrator who desires to setup a more customized andspecific network may specify declarative requirements at a lowerstage/level (e.g., specific cable connection mapping between networkswitches).

In some embodiments, each stage processes an input requirement using oneor more constraints (e.g., resources available, policies to follow,etc.) to determine the output requirement. In some embodiments,constraints are received at the interaction agent. For example, a userprovides the constraints (e.g., resources available, policies to follow,etc.) for storage in a data store for use in one or more processingstages. In some embodiments, if a required declarative requirement hasnot been specified by a user, a default declarative requirement that isconsistent with the specified declarative requirement is utilized. Insome embodiments, declarative requirements may be specified for aplurality of different processing stages/levels. For example, a user mayspecify a high level declarative requirement for the starting processingstage/level but also for another lower processing stage/level tocustomize a desired aspect. In some embodiments, the declarativerequirements are specified in JavaScript Object Notation (i.e., JSON)format.

At 204, at least a portion of the set of network requirements ispublished to a system data store. For example, the set of networkrequirements is published to data store 104 of FIG. 1. In someembodiments, one or more received constraints are published to a systemdata store. In some embodiments, one or more constraints may beautomatically determined. In some embodiments, the interaction agent isstateless. For example, the interaction agent does not maintain its ownstorage that tracks states of requirement processing and communication.Rather than store and keep track of its state data, the state data isstored/published to a remote network data store (e.g., data store 104 ofFIG. 1). By being stateless, the interaction agent may be quicklyreplaced/restarted when it encounters an error without the need torestore state information in the replaced component.

In some embodiments, publishing the set of network requirements and/orconstraints includes storing the set of network requirements and/orconstraints in the system data store to allow an application agent toread and access the published set of requirements and/or constraints.Thus, rather than directly communicating the set of network requirementsto the application agent, the interaction agent publishes the set ofrequirements to the storage to communicate the information to theapplication agent. In some embodiments, publishing the set ofrequirements includes selecting one or more application agents that areto receive appropriate network requirements. For example, there exists aplurality of different application agents and each application agentperforms a different type of processing and/or processing for adifferent set of one or more network devices. In another example, thesame and/or different application agents may perform each processingstage/level of a plurality of different processing stages/levels. Inorder to achieve/complete the set of network requirements, the set ofnetwork requirements may need to be routed to the appropriateapplication agent for further processing. In some embodiments, the setof network requirements is processed to identify which application agentshould receive which portion (or all) of the set of requirements and therequirement(s) to be received by each appropriate application agent ispublished to a different storage location or identified by a differentidentifier of the system data store corresponding to the appropriateapplication agent. For example, the data store includes different datarecords corresponding to each different application agent andrequirement(s) may be communicated to an application agent by publishingrequirements to the corresponding data record of the desired applicationagent. In another example, an identifier included in the published dataidentifies which application agent should receive the published data. Insome embodiments, one or more other network requirements associated withthe received set of network requirements are determined and published.For example, a default network requirement for one or more associatedprocessing stages/levels of the received set of network requirements isautomatically determined and published for processing.

In some embodiments, the received set of requirements and/or constraintsis modified prior to being published. For example, the received set ofnetwork requirements is translated into a form that can be published toa data store. In another example, additional requirements determined tobe required to achieve the received set of requirements are added. Inanother example, one or more requirements determined to be not requiredto achieve the received set of requirements are removed. In anotherexample, one or more requirements of the received set of requirementsare modified.

In some embodiments, publishing the set of requirements includesstoring/creating an identifier in the system data store that identifiesthe status of one or more requirements of the set of networkrequirements. For example, an identifier is stored in the system datastore that identifies that the set of network requirements has beenpublished in the system data store and is ready to be processed by oneor more application agents. As the set of network requirements isprocessed by an application agent and other agents, the statusidentifier may be updated by an application agent or other agents toprovide an update of the status of achieving/completing thecorresponding requirements.

FIG. 2B is a flowchart illustrating an embodiment of a process forprocessing requirements. The process of FIG. 2B may be implemented onmanagement server 102 of FIG. 1. In some embodiments, the process ofFIG. 2B is performed by interaction agent 112 of FIG. 1.

At 212, constraints are received. In some embodiments, one or moreconstraints are received from a user via an interface. For example,constraints (e.g., resources available, policies to follow, etc.) arereceived at the interaction agent via a user interface (e.g., webinterface, application interface, command line interface, applicationprogramming interface (API), RESTful API, configuration file interface,etc.). In some embodiments, the constraints have been automaticallydetermined. For example, the constraints include a list of networkswitches available and the available resources have been automaticallydiscovered. In some embodiments, the constraints include informationidentifying resources. For example, identification information abouthardware and/or software resources available to be utilized to determinean output declarative requirement is received. In some embodiments, theconstraints include specification of one or more policies. For example,a policy specification of how to determine an output requirement isspecified by a policy constraint (e.g., how to assign device names, howto assign port mappings, etc.). In some embodiments, the policyconstraint may include one or more rules, logic, program code, and/ormappings that at least in part specify how to determine an output froman input declarative requirement. In some embodiments, the constraintsmay be utilized together with an input declarative requirement by anapplication agent to determine an output requirement for at least oneprocessing stage/level of a plurality of processing stages/levels of theapplication agent. In some embodiments, the received constraint isassociated with at least one specific processing stage/level.

At 214, the received constraints are stored. In some embodiments,storing the received constraints includes publishing the constraints toa system data store. For example, the constraints are published to datastore 104 of FIG. 1. In some embodiments, publishing the constraintsincludes storing the constraints in the system data store to allow anapplication agent to read and access the published constraints for useduring one or more processing stages/levels. Thus rather than directlycommunicating the constraints to the application agent, the interactionagent publishes the set of requirements to the storage to communicatethe information to the application agent. In some embodiments,publishing the constraints includes selecting one or more applicationagents that are to receive appropriate constraints. For example, thereexists a plurality of different application agents and each applicationagent performs a different type of processing and/or processing for adifferent processing stage/level. In another example, the same and/ordifferent application agents may perform each processing stage/level ofa plurality of linked processing stages/levels. In some embodiments,publishing the constraints includes selecting one or more processingstages/levels that will be utilizing one or more appropriateconstraints. In some embodiments, the received constraints are modifiedprior to being published. For example, the received constraints aretranslated into a form that can be published to a data store. In anotherexample, additional constraints determined to be required for processingare added. In another example, one or more constraints determined to benot required are removed.

FIG. 3A is a flowchart illustrating an embodiment of a process forpublishing device requirements. The process of FIG. 3A may beimplemented on management server 102 of FIG. 1. In some embodiments, theprocess of FIG. 3A is performed by application agent 114 of FIG. 1. Insome embodiments, the process of FIG. 3A is performed for each set ofnetwork requirements to be processed by one or more application agents.In some embodiments, the process of FIG. 3A is performed for eachdeclarative requirement processing stage/level of a plurality ofsuccessive processing stages/levels.

At 302, a set of network requirements is received at an applicationagent. In some embodiments, the application agent is application agent114 of FIG. 1. In some embodiments, the application agent is a softwareand/or hardware component that manages desired requirements,configurations, and status updates across various network devices. Forexample, the application agent provides instructions to and receivesstatus information from various devices of a network being managed. Insome embodiments, different types of application agents that performdifferent functions may exist. For example, network requirements areprovided to a specific application agent by matching the requirements tothe specific functionality of the specific application agent.

In some embodiments, the received set of requirements is the set ofrequirements published in 204 of FIG. 2A. In some embodiments, receivingthe set of network requirements includes receiving an indication thatthe set of requirements has been stored in a data store for theapplication agent. For example, a system data store such as data store104 of FIG. 1 includes a data record where data for the applicationagent can be published and/or the system data store recognizes where apublished data should be routed based on an included identifier. Eachdifferent application agent may subscribe to one or more data records ofthe system data store and/or subscribe to one or more identifiers thatidentify content to be routed to the subscribed application agent. Inone example, the system data store includes a different data record foreach different application agent and the each application agentsubscribes to at least its corresponding data record. In anotherexample, each application agent subscribes to an identifier and thesystem data store routes published data with the identifier to thesubscribed application agent.

In some embodiments, by subscribing to a data record, the applicationagent may be provided a notification by the data storage in the eventdata is published to a subscribed data record and/or includes asubscribed data identifier. In some embodiments, by subscribing to adata record and/or a data identifier, the application agent may beautomatically provided/sent any data published to the subscribed datarecord and/or identified by the data identifier. In some embodiments,the receiving the set of network requirements includes receiving anindication that the set of network requirements of interest has beenstored in the data store and the application agent requests and obtainsthe set of network requirements of interest. For example, the set ofnetwork requirements for a specific processing stage/level to beprocessed by the application agent is received. In some embodiments, thereceiving the set of network requirements includes automaticallyreceiving content of the set of network requirements subscribed by theapplication agent. In some embodiments, receiving the set ofrequirements includes directly receiving the set of requirements from aninteraction agent.

In some embodiments, the set of requirements is a set of declarativerequirements that specifies a desired configuration, a desired action, adesired mapping result, a command, or any other desired result of adeclarative requirement processing stage/level. In some embodiments, theset of declarative requirements has been specified for a selectedprocessing stage/level. For example, there exists a plurality ofsuccessive processing stages/levels that successively require morespecific/lower level declarative requirements at each lower level and auser may specify declarative requirements for any one of thestages/levels. In some embodiments, the set of requirements was notcompletely specified by a user and the received set of requirementsincludes a default declarative requirement that is consistent with userspecified declarative requirements.

At 304, one or more constraints associated with the set of networkrequirements are received. For example, constraints (e.g., resourcesavailable, policies to follow, etc.) that are to be utilized with thereceived set of requirements to determine an output are identified andreceived. In some embodiments, the one or more constraints have beenidentified based at least in part on a processing stage/level associatedwith the set of network requirements to be processed by the applicationagent. In some embodiments, the received set of constraints is the setof constraints stored in 214 of FIG. 2B.

At 306, the received set of network requirements and the received one ormore constraints are utilized to determine a set of output requirements.For example, the received set of input requirements and the received oneor more applicable constraints are utilized to determine a lower levelof output declarative requirements. In some embodiments, the receivedset of network requirements is a set of declarative requirements thatare to be processed using the one or more constraints to ultimatelydetermine a set of declarative device requirements for one or moredevices to be configured to implement a desired network. In someembodiments, a linear progression of one or more processingstages/levels is followed to determine a final output set of declarativerequirements. In some embodiments, a directed graph progression of oneor more processing stages/levels is utilized determine a final outputset of declarative requirements. For example, a workflow processingorder of a directed acyclic graph of one or more processingstages/levels is followed to determine the final output set ofdeclarative requirements.

In one example, the set of requirements to establish the L3 Clos networkconfiguration described previously is received at the application agentand the application agent analyzes the received requirements anddetermines and identifies devices that will be utilized to implement thedesired network configuration of the received network requirements. Theexample L3 Clos network requirements specify the number of spine networkswitch devices to be 16 and the number of leaf network switch devices tobe 128. In total, the application agent will determine and identify 144devices that will need to be configured to implement the desired Closnetwork. For each of the devices that are to be utilized, theapplication agent determines the individual device requirements inimplementing the desired Clos network. The individual devicerequirements may be stored in a corresponding system data store entryfor each device. For example, the application agent publishes theindividual device requirements in 144 different data entries of the datastore and each proxy agent of each device accesses these data entries toreceive the corresponding device requirements. For the L3 Clos networkexample, below is one example of device requirements for one of the 144different device requirements.

-   -   Role=spine    -   IP address=10.0.0.3    -   Neighbors=[(Leaf-1, 10.0.0.7), (Leaf-2, 10.0.0.15), . . .        (Leaf-128, 10.0.0.176)]    -   Status=defined        The above device requirements specify that in a Clos network,        one network switch device is to be a spine switch with IP        address 10.0.0.3. The leaf switches connected to this spine        switch device have been also identified.

In some embodiments, the processing performed in 306 includes performingprocessing for at least one processing stage/level of a plurality ofsuccessive declarative requirement processing stages/levels. Forexample, a processing for one processing stage/level is performed usingthe application agent and the output declarative requirement of thisprocess level is published to a data store for use as an inputdeclarative requirement for the next processing stage, if applicable. Inanother example, the application agent performs processing for aprocessing stage/level that utilizes the received set of networkrequirements as an input and also performs processing for subsequentlower level processing stages/levels that each utilize outputdeclarative requirements of a previous higher level processingstage/level as its input declarative requirements until a lastprocessing stage/level determines a set of declarative devicerequirements for one or more devices to be configured to implement adesired network. If a declarative requirement is not specified for aparticular processing stage/level, the required input declarativerequirement for the processing stage/level may be determinedautomatically based on the received declarative requirements (e.g., tobe consistent) and/or a default declarative requirement for theprocessing stage/level is utilized.

In some embodiments, utilizing the one or more constraints includesutilizing information identifying resources to assign a configurationto/from hardware/software resources. For example, devices to beconfigured are selected from a list of device resources. In anotherexample, a configuration parameter is selected from a list of availableconfiguration parameter ranges. In some embodiments, utilizing theconstraint includes utilizing a specification of one or more policies.For example, a policy specification of how to determine the outputrequirement from the input requirements is specified by a policy (e.g.,how to assign device names, how to assign port mappings, etc.). In someembodiments, a policy includes one or more rules, logic, program code,and/or mappings that at least in part specify how to determine theoutput declarative requirements from the input declarative requirements.

In some embodiments, the application agent utilized to determine theoutput requirements is configurable/customizable. For example, a usermay modify, extend, and/or configure the processing performed by theapplication agent and/or define the entire application agent. Theapplication agent may be configurable/customizable via an interface suchas an API.

In some embodiments, the set of output requirements is verified. In someembodiments, verifying the set of output requirements includesperforming one or more tests to determine whether the set of outputrequirements is valid and matches an intent of input requirement(s). Insome embodiments, the test to be performed may depend on the processingstage/level of the set of output requirements, content of the inputrequirements, content of the output requirements, the application agentutilized, one or more constraints utilized, and/or processing performedto determine the output declarative requirements.

In some embodiments, the final processing stage/level of the pluralityof processing stages/levels generates the set of output requirementsthat includes requirements for one or more devices (e.g., devicesdetermined and selected by device type, capability, quantity required,processing capability, etc. required to implement received requirements)that will be utilized to implement the desired network of the inputrequirements. For each of the one or more devices that are to beconfigured, individual device requirements may be determined. In someembodiments, the device requirements for each individual device aredeclarative requirements. For example, the device requirements include aspecification of a desired configuration, setting, and/or otherspecifications of a network device.

At 308, the set of output requirements corresponding to the receivedrequirements are published to a system data store. In some embodiments,the set of output requirements is to be utilized as input requirementsfor a next processing level and is published to be provided to anapplication agent to process the next processing stage/level. In someembodiments, the set of output requirements includes device requirementsfor one or more devices that are to be configured to implement thereceived network requirements. For example, the application agentanalyzes the received network requirements and determines (e.g., usingone or more processing stages/levels) one or more devices (e.g., devicesdetermined and selected by device type, capability, quantity required,processing capability, etc. required to implement received requirements)that will be utilized to implement the received network requirements.For each of the one or more devices that are to be configured, theapplication agent determines its individual device requirements.

In some embodiments, the device requirements for each individual deviceare declarative requirements. For example, the device requirementsinclude a specification of a desired configuration, setting, and/orother specifications of a network device. The declarative requirementsexpress a desired configuration of a network device without specifyingan exact native device configuration and control flow instructions. Byutilizing declarative requirements, what should be accomplished in thenetwork device is specified rather than exact native hardwareinstructions. By utilizing declarative requirements rather thanimperative instructions, the application agent is relieved of the burdenof determining the exact device programming and configuration syntaxrequired to achieve a desired result. For example, it is often difficultand burdensome for a user to know the exact imperative syntax andconfiguration paradigm to configure each device of a network whenvarious different types of devices from different vendors may beutilized and interchanged dynamically on the network.

In some embodiments, publishing the set of output requirements includesstoring the output requirements in a system data store (e.g., data store104 of FIG. 1) to allow one or more application agents and/or proxyagents to read and access the published set of requirements. Thus ratherthan directly communicating the device requirements to anotherapplication agent or one or more selected devices that will be utilizedto implement the desired network, the application agent publishes thedevice requirements to the system storage to communicate theinformation.

In some embodiments, publishing the set of output requirements includesselecting one or more application/proxy agents that are to receiveapplicable requirements. For example, there exists a plurality ofdifferent proxy agents that are each assigned to a different device ofthe network. In order to achieve and implement the desired networkrequirements, the corresponding device requirements may need to berouted to the appropriate proxy agents for further processing. Thedevice requirements to be received by each appropriate application/proxyagent may be published to different storage locations of the system datastore corresponding to the appropriate application/proxy agent. Forexample, the system data store includes different data recordscorresponding to each different application/proxy agent and appropriaterequirements may be communicated to a corresponding proxy agent bypublishing the appropriate requirements to the corresponding data recordof the desired application/proxy agent.

In some embodiments, requirements for an application agent are publishedusing an identifier that identifies the application agent that isreceiving the requirements. In some embodiments, publishing therequirements includes storing/creating an identifier in the system datastore. In some embodiments, a status identifier may be updated by theapplication agent as the requirements are achieved/completed. Forexample, an identifier is stored in the system data store thatidentifies that the requirements for an application agent have beenpublished in the system data store and are ready to be processed by anappropriate application agent (e.g., set in “defined” state). As therequirements are processed by the application agent, the statusidentifier may be updated by the application agent to provide an updateof the status of completing the processing stage of the requirements.

In some embodiments, device requirements for each device/proxy agent arepublished using an identifier that identifies the device/proxy agentthat is receiving the corresponding device requirements. In someembodiments, publishing the device requirements includesstoring/creating an identifier in the system data store for each devicerequirement of devices to be utilized to implement the received networkrequirements. The published “Status” device requirement in the previousL3 Clos network example specifies a status of achieving the devicerequirement. This status identifier may be updated by a proxy agent ofthe network switch device as the device requirements areachieved/completed. For example, an identifier is stored in the systemdata store that identifies that the device requirements for a devicehave been published in the system data store and are ready to beprocessed by an appropriate proxy agent (e.g., set in “defined” state).As the device requirements are processed by the proxy agent, the statusidentifier may be updated by the proxy agent to provide an update of thestatus of achieving the device requirements.

FIG. 3B is a flowchart illustrating an embodiment of an example processfor automatically configuring a network using received declarativerequirements. The process of FIG. 3B may be implemented on managementserver 102 of FIG. 1. In some embodiments, the process of FIG. 3B isperformed at least in part by one or more different application agentssuch as application agent 114 of FIG. 1. For example, each processingstage/level may be performed by the same application agent or bydifferent application agents. In some embodiments, at least a portion ofthe process of FIG. 3B is included in 306 of FIG. 3A. In someembodiments, the process of FIG. 3B is utilized to automaticallyconfigure an L3 ClosClos network. For example, the process of FIG. 3B isutilized to configure an L3 ClosClos network for a specific networkdomain and network point of delivery (i.e., PoD).

In some embodiments, the process of FIG. 3B may be flexiblystarted/entered at any of the steps of the process depending upon alevel of input declarative requirements provided by a user. In someembodiments, after declarative requirements to configure a network arereceived (e.g., received at 202 of FIG. 2A), the processing stage/levelof the declarative requirement processing stages/levels corresponding tothe received declarative requirements is determined (e.g., declarativerequirements are published in 204 of FIG. 2A for the specificapplication agent to process the declarative requirement for theidentified processing stage/level). For example, the receiveddeclarative requirements are analyzed to determine the level/type ofrequirements specified in the received declarative requirements and theprocessing stage/level of a plurality of processing stages/levelscorresponding to the received declarative requirements is identified. Insome embodiments, it is determined which step (e.g., which one of steps310 to 320) of the process of FIG. 3B corresponds to the identifiedprocessing stage/level and the process of FIG. 3B is entered/started atthe determined step.

At 310, processing for a logical connectivity processing stage/level isperformed to determine an output defining logical connectivity. In someembodiments, the logical connectivity is determined at a processingstage/level of a plurality of declarative requirement processingstages/levels. In some embodiments, processing the logical connectivityprocessing stage/level includes determining output declarativerequirements using input declarative requirements. In some embodiments,the input declarative requirements are at least in part received in 302of FIG. 3A. In some embodiments, processing the logical connectivityprocessing stage/level includes determining output declarativerequirements identifying logical connections between leaf networkswitches and spine network switches to implement input declarativerequirements defining a desired L3 Clos network. The input declarativerequirements of this processing stage/level may specify one or more ofthe following: the number of servers to be connected using the L3 Closnetwork to be established; and the oversubscription ratio (e.g., maximumamount of bandwidth theoretically that could be required for a networkswitch port vs. actual maximum bandwidth capacity of the network switchport). In some embodiments, constraints are obtained (e.g., obtained in304 of FIG. 3A) and utilized (e.g., utilized in 306 of FIG. 3A) todetermine the output declarative requirements. For example, profiles(e.g., number of up ports, number of down ports, etc.) of devices (e.g.,network hardware switches) available to be utilized to create the L3Clos network (e.g., without identifying specific exact machine) areobtained and utilized in selecting the types of devices to be utilizedin the output declarative requirement identifying the mesh network. Insome embodiments, only devices identified in the constraints may be theswitches identified in the output declarative requirements.

In some embodiments, the input declarative requirements of the logicalconnectivity processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the logical connectivity processing stage/level includedeclarative requirements received in 202 of FIG. 2A. In someembodiments, at least a portion of the input declarative requirementshas not been directly specified by a user and a default and/ordynamically determined declarative input requirement is utilized. Thedynamically determined declarative input requirement may be determinedto be consistent with at least in part a user provided input declarativerequirement. In some embodiments, step 310 is not performed in the eventa user provided a lower/later level/stage of input declarativerequirements. For example, the process of FIG. 3B is entered at 312. Insome embodiments, the output declarative requirements are verified toensure performance expectations and/or an intent of the inputdeclarative requirements are met. In some embodiments, the outputdeclarative requirements are verified to verify the number and/or typeof network switches utilized and/or devices utilized in the outputdeclarative requirements.

At 312, processing for a physical connectivity processing stage/level isperformed to determine an output defining a physical connectivity. Insome embodiments, the physical connectivity processing stage/level isone of a plurality of declarative requirement processing stages/levels.In some embodiments, processing the physical connectivity processingstage/level includes determining output declarative requirements usinginput declarative requirements. The input declarative requirements ofthis processing stage/level may be the output declarative requirementsof the processing stage/level of 310. In some embodiments, the inputdeclarative requirements are at least in part received in 302 of FIG.3A. In some embodiments, processing the physical connectivity processingstage/level includes determining an output declarative requirementidentifying physical connections between specific device typescorresponding to logical connections specified in the input declarativerequirements. In some embodiments, constraints are obtained (e.g.,obtained in 304 of FIG. 3A) and utilized (e.g., utilized in 306 of FIG.3A) to determine the output declarative requirements. For example,profiles (e.g., device names, etc.) of specific device types (e.g.,specific model/vendor of network hardware switches) available to beutilized to create the L3 Clos network are obtained and utilized inselecting the specific device types and/or device names to be utilizedin the output declarative requirement identifying the L3 Clos meshnetwork. In some embodiments, specific device names and device types areassigned to logical devices of the input declarative requirements todetermine the output declarative requirements for this processing stage.

In some embodiments, the input declarative requirements of the physicalconnectivity processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the physical connectivity processing stage/level includedeclarative requirements received in 202 of FIG. 2A. In someembodiments, at least a portion of the input declarative requirementshas not been directly specified by a user and a default and/ordynamically determined declarative input requirement is utilized. Thedynamically determined declarative input requirement may be determinedto be consistent with at least in part a user provided input declarativerequirement. In some embodiments, step 312 is not performed in the eventa user provided a lower/later level/stage of input declarativerequirements than the level of the physical connectivity processingstage/level. For example, the process of FIG. 3B is entered at 314. Insome embodiments, the output declarative requirements are verified toensure correct route tables are consistent with the input declarativerequirements. In some embodiments, the output declarative requirementsare verified to verify route tables, specific device types, and/ordevice names included in the output declarative requirements.

At 314, processing for a cabling diagram processing stage/level isperformed to determine an output defining a cabling map. In someembodiments, the cabling diagram processing stage/level is one of aplurality of declarative requirement processing stages/levels. In someembodiments, processing the cabling diagram processing stage/levelincludes determining output declarative requirements using inputdeclarative requirements. The input declarative requirements of thisprocessing stage/level may be the output declarative requirements of theprocessing stage/level of 312. In some embodiments, the inputdeclarative requirements are at least in part received in 302 of FIG.3A. In some embodiments, processing the cabling diagram processingstage/level includes determining an output declarative requirementidentifying a cabling map defining connections between ports of L3 Closswitches specified in the input declarative requirements. In someembodiments, constraints are obtained (e.g., obtained in 304 of FIG. 3A)and utilized (e.g., utilized in 306 of FIG. 3A) to determine the outputdeclarative requirements. For example, constraints of portmaps/identifications and port resources of specific devices (e.g.,network hardware switches) to be utilized to create the L3 Clos networkare obtained and utilized in determining the specific cable connectionsbetween ports of the switches of the L3 Clos mesh network. In someembodiments, various roles (e.g., server facing, spine, edge, etc.) areassigned for specific ports in determining the output declarativerequirements for this processing stage. In some embodiments, one or morepolicies/rules/code constraints are utilized in determining the cablingdiagram output declarative requirement.

In some embodiments, the input declarative requirements of the cablingdiagram processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the cabling diagram level include declarativerequirements received in 202 of FIG. 2A. In some embodiments, at least aportion of the input declarative requirements has not been directlyspecified by a user and a default and/or dynamically determineddeclarative input requirement is utilized. The dynamically determineddeclarative input requirement may be determined to be consistent with atleast in part a user provided input declarative requirement. In someembodiments, step 314 is not performed in the event a user provided alower/later level/stage of input declarative requirements than the levelof the physical connectivity processing stage/level. For example, theprocess of FIG. 3B is entered at 316. In some embodiments, the outputdeclarative requirements are verified to ensure correct cabling and/orport (e.g., port function) mappings.

At 316, processing for a candidate requirement processing stage/level isperformed to determine an output defining soft resource assignments. Insome embodiments, the candidate requirement processing stage/level isone of a plurality of declarative requirement processing stages/levels.In some embodiments, processing the candidate requirement processingstage/level includes determining output declarative requirements usinginput declarative requirements. The input declarative requirements ofthis processing stage/level may be the output declarative requirementsof the processing stage/level of 314. In some embodiments, the inputdeclarative requirements are at least in part received in 302 of FIG.3A. In some embodiments, processing the candidate requirement processingstage/level includes determining an output declarative requirementidentifying assigned soft resources of connections identified in theinput declarative requirements. In some embodiments, constraints areobtained (e.g., obtained in 304 of FIG. 3A) and utilized (e.g., utilizedin 306 of FIG. 3A) to determine the output declarative requirements. Forexample, constraints including a listing of soft resources (e.g., IPaddress ranges, autonomous system number (ASN) ranges, etc.) availableto be assigned are utilized in assigning soft resources to the networkswitch connections. In some embodiments, one or more policies/rules/codeconstraints are utilized in assigning soft resources specified in theoutput declarative requirements.

In some embodiments, the input declarative requirements of the candidaterequirement processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the candidate requirement level include declarativerequirements received in 202 of FIG. 2A. In some embodiments, at least aportion of the input declarative requirements has not been directlyspecified by a user and a default and/or dynamically determineddeclarative input requirement is utilized. The dynamically determineddeclarative input requirements may be determined to be consistent withat least in part a user provided input declarative requirement. In someembodiments, step 316 is not performed in the event a user provided alower/later level/stage of input declarative requirements than the levelof the physical connectivity processing stage/level. For example, theprocess of FIG. 3B is entered at 318. In some embodiments, the outputdeclarative requirements are verified to ensure correct IP assignments,ASNs, Border Gateway Protocol (BGP) sessions, etc.

At 318, processing for a rendered requirement processing stage/level isperformed to determine an output defining any extended/optionalrequirements. In some embodiments, the rendered requirement processingstage/level is one of a plurality of declarative requirement processingstages/levels. In some embodiments, processing the rendered requirementprocessing stage/level includes determining output declarativerequirements using input declarative requirements. The input declarativerequirements of this processing stage/level may be the outputdeclarative requirements of the processing stage/level of 316. In someembodiments, the input declarative requirements are at least in partreceived in 302 of FIG. 3A. In some embodiments, processing the renderedrequirement processing stage/level includes determining an outputdeclarative requirement identifying final configurations including anyextended/optional requirements/configurations of the L3 Clos network tobe established. In some embodiments, constraints are obtained (e.g.,obtained in 304 of FIG. 3A) and utilized (e.g., utilized in 306 of FIG.3A) to determine the output declarative requirements. For example, aspecification of extended/optional configurations (e.g., configurationto be added/substituted from candidate configurations, parameters, etc.)to be assigned for specific types of devices is utilized in determiningextended/optional requirements/configurations of the final requirementsspecified in the output declarative requirements. In some embodiments,one or more policies/rules/code constraints are utilized in determiningthe rendered requirement output declarative requirements.

In some embodiments, the input declarative requirements of the renderedrequirement processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the rendered requirement level include declarativerequirements received in 202 of FIG. 2A. In some embodiments, at least aportion of the input declarative requirements has not been directlyspecified by a user and a default and/or dynamically determineddeclarative input requirement is utilized. The dynamically determineddeclarative input requirement may be determined to be consistent with atleast in part a user provided input declarative requirement. In someembodiments, step 318 is not performed in the event a user provided alower/later level/stage of input declarative requirements than the levelof the physical connectivity processing stage/level. For example, theprocess of FIG. 3B is entered at 320. In some embodiments, the outputdeclarative requirements are verified to ensure correct finalconfigurations.

At 320, processing for a validated requirement processing stage/level isperformed to determine an output including specific device requirements.In some embodiments, the validated requirement processing stage/level isthe final processing stage/level of a plurality of declarativerequirement processing stages/levels. In some embodiments, processingthe validated requirement processing stage/level includes determiningoutput declarative requirements using input declarative requirements.The input declarative requirements of this processing stage/level may bethe output declarative requirements of the processing stage/level of318. In some embodiments, the input declarative requirements are atleast in part received in 302 of FIG. 3A. In some embodiments,processing the validated requirement processing stage/level includesdetermining an output declarative requirement assigning finalconfigurations to specific network devices to be configured to implementthe L3 Clos network. In some embodiments, constraints are obtained(e.g., obtained in 304 of FIG. 3A) and utilized (e.g., utilized in 306of FIG. 3A) to determine the output declarative requirements. Forexample, constraints including a specification of specific deviceprofiles, availability of specific actual devices, and/or uniqueidentifiers of (e.g., serial numbers) of specific devices are receivedto determine specific device/switch assignments to be specified in theoutput declarative requirements. In some embodiments, one or morepolicies/rules/code constraints are utilized in assigning specificdevices assigned in the validated requirement output declarativerequirements.

In some embodiments, the input declarative requirements of the validatedrequirement processing stage/level include one or more declarativerequirements provided by a user. For example, the input declarativerequirements of the rendered requirement level include declarativerequirements received in 202 of FIG. 2A. In some embodiments, at least aportion of the input declarative requirements has not been directlyspecified by a user and a default and/or dynamically determineddeclarative input requirement is utilized. The dynamically determineddeclarative input requirements may be determined to be consistent withat least in part a user provided input declarative requirement. In someembodiments, step 320 is not performed in the event a user providesfinal validated requirements identifying specific devices. In someembodiments, the output declarative requirements are verified to ensurecorrect specific device assignments. In some embodiments, the outputdeclarative requirements are to be pushed to specific proxy agents toconfigure specific devices/switches. For example, the output declarativerequirements of this stage/level are received at 402 of FIG. 4.

Although a simple liner progression of processing stages/levels havebeen shown in the example of FIG. 3B, in a different example, a directedgraph progression of one or more processing stages/levels is utilizeddetermine final output declarative requirements. For example, a workflowprocessing order of a directed acyclic graph of one or more processingstages/levels is followed to determine the final output set ofdeclarative requirements.

FIG. 3C is a block diagram illustrating processing stages/levels of anexample process for automatically configuring an L3 Clos network. Theprocessing shown in FIG. 3C may be implemented on management server 102of FIG. 1. In some embodiments, the processing shown in FIG. 3C isperformed at least in part by one or more different application agentssuch as application agent 114 of FIG. 1. In some embodiments, theprocessing shown in FIG. 3C is included in 306 of FIG. 3A. In someembodiments, FIG. 3C illustrates the process of FIG. 3B. In someembodiments, a user is able to flexibly enter the processing shown inFIG. 3C at any one of the successive processing stages/levels dependingon a level of input declarative requirements provided by a user. Asshown in diagram 330, output declarative requirements of aprevious/higher level stage are utilized by an application agent of thenext lower level as its input declarative requirements. The applicationagents utilize the input declarative requirements along with predefinedinput constraints to determine the output declarative requirements.

FIG. 4 is a flowchart illustrating an embodiment of a process forgenerating native hardware instructions. The process of FIG. 4 may beimplemented on network device 106 and/or 108 of FIG. 1. In someembodiments, the process of FIG. 4 is performed by proxy agent 116and/or 118 of FIG. 1.

At 402, device requirements are received at a proxy agent. In someembodiments, the proxy agent is proxy agent 116 or 118 of FIG. 1. Insome embodiments, the proxy agent is a software and/or hardwarecomponent that manages and implements device requirements for anassociated/assigned device. In some embodiments, differenttypes/versions of proxy agents exist for different network devices. Forexample, a proxy agent provides conversion functionality between adevice requirement and implementing native instructions specific to adevice and the proxy agent that can generate native instructions for aspecific device (e.g., specific to vendor, operating system, protocol,version, etc. of the device) is selected for the specific device. Byseparating functionality between the interaction agent, applicationagent, and proxy agent, only the proxy needs to handle specific nativeinstructions of a device. Thus, when a new type or version of a deviceis added to a network, only a new proxy agent for the new device isrequired while the interaction agent and application agent may remainunchanged. This may allow simplified administration of various differenttypes of devices of a network. The proxy agent may be installed on adevice managed by the proxy agent. In some embodiments, the proxy agentis remote from the managed device. In some embodiments, one proxy agentmay manage a plurality of devices. For example, a single proxy agent maymanage a plurality of devices of the same type.

In some embodiments, the received device requirements are the devicerequirements published in 308 of FIG. 3A for a device of the proxyagent. In some embodiments, receiving the device requirements includesreceiving an indication that the device requirements have been stored ina system data store for the proxy agent of a specific device. Forexample, a system data store such as data store 104 of FIG. 1 includes adata record where data for the proxy agent can be published. Eachdifferent proxy agent may subscribe to one or more data records of thesystem storage that correspond to a device being managed by therespective proxy agent. For example, the system data store includes adifferent data record for each device of the network and the each proxyagent subscribes to the corresponding data record of its assigneddevice. In some embodiments, each different proxy agent subscribes withthe system data store one or more identifiers that identify the deviceassociated with the corresponding proxy agent. For example, anypublished data identified by the subscribed identifier is notified tothe subscribed proxy agent. In some embodiments, by subscribing to adata record and/or an identifier, the proxy agent may be provided anotification by the data store in the event data is published to thesubscribed data record and/or data associated with the identifier hasbeen published. In some embodiments, by subscribing to a data recordand/or an identifier, the proxy agent may be automatically provided/sentany data published to the subscribed data record and/or identified bythe identifier. In some embodiments, the receiving the devicerequirements includes receiving an indication that the devicerequirements have been stored to a data store due to a subscription andthe proxy agent requests and obtains the device requirements from thedata store. In some embodiments, the receiving the device requirementsincludes automatically receiving content of device requirements from adata store due to a subscription. In some embodiments, receiving thedevice requirements includes directly receiving the device requirementsfrom an application agent.

At 404, native hardware instructions are generated at the proxy agent toconfigure a device of the proxy agent. In some embodiments, the devicerequirements received by the proxy agent are processed by the proxyagent to generate the native hardware instructions implementing thereceived device requirements. For example, received declarativeinstructions are converted to imperative instructions. In someembodiments, the native hardware instructions are in the nativeprogramming/configuration syntax of the device. For example, the nativehardware instructions are generated in a format native to aconfiguration software interface of the device. In some embodiments, thenative hardware instructions are instructions that can beunderstood/processed by a software component of the device to configurethe device. In some embodiments, the native hardware instructions are ina form that can be directly utilized by the device to configure thedevice. In some embodiments, the native hardware instructions areexecuted by the device. For example, the generated native hardwareinstructions are issued for execution on the device.

In one example, the device requirements to become a spine switch of theL3 Clos network configuration described previously in the specificationare received at the proxy agent and the proxy agent analyzes thereceived device requirements and generates native network switch deviceinstructions to configure the network switch device to become a spineswitch of a Clos network with the specified IP address and specifiedneighbors.

At 406, a status of the device is provided. In some embodiments, step406 is optional and may not be performed. In some embodiments, providingthe status includes publishing an identifier of the status to a systemdata store (e.g., data store 104 of FIG. 1). In some embodiments,providing the status includes providing an indication of status ofachieving the received device requirements. For example, a statusindication of a stage of the processing of the device requirements isprovided. In some embodiments, providing the status indication includesupdating a status identifier in a system data store. For example, astatus identifier is updated in data store 104 of FIG. 1 (e.g., allowingthe proxy agent to be stateless). In some embodiments, the updatedstatus identifier is the identifier corresponding to the“Status=defined” published in the Clos network device requirementexample described previously.

In some embodiments, the status of the device indicates a status ofimplementing device requirements on the device. For example, the statusmay be one of six states. The initial first example state is a “defined”state that indicates that the device requirement has been successfullypublished to a system data store by an application agent. A secondexample state is a “staged” state that is indicated by a receiving proxyagent that the proxy agent has received the device requirements and hasallocated resources to implement the device requirements. A thirdexample state is a “rendered” state that indicates that the proxy agenthas generated native hardware instructions corresponding to the devicerequirements. A fourth example state is a “deployed” state thatindicates that the proxy agent has issued the generated native hardwareinstructions for execution on the device. A fifth example state is anoperational state that indicates that the generated native hardwareinstructions are successfully executed on the device. However, when anerror is encountered, a sixth example “error” state may be indicated toindicate that an error has been encountered.

In some embodiments, the status of the device indicates a health stateof the device. For example, indication of information such as processingload, CPU utilization, storage utilization, memory utilization, versionidentification, errors encountered, network status, network bandwidth,network latency, etc. may be provided. In some embodiments, the statusof the device indicates a packet drop rate. For example, an indicationof a Ternary Content Addressable Memory (i.e., TCAM) utilization of thedevice is provided by the proxy agent. In another example, an indicationis provided when a TCAM table is overflowed.

FIG. 5 is a flowchart illustrating an embodiment of a process forverifying an expectation. The process of FIG. 5 may be implemented onmanagement server 102 of FIG. 1. In some embodiments, the process ofFIG. 5 is performed at least in part by application agent 114 of FIG. 1.

At 502, a status of a device is received. In some embodiments, thestatus of the device is a status of a resource of the device. In someembodiments, the status of the device is a status of device requirementsbeing implemented by the device. In some embodiments, the status of thedevice is a status of any errors of the device. In some embodiments, thestatus of the device is the status provided in 406 of FIG. 4. In someembodiments, the received status is one of a plurality of statusesreceived from the same proxy agent or different proxy agents of one ormore different devices.

In some embodiments, the status is received via a system data store suchas data store 104 of FIG. 1. For example, the application agent hassubscribed with the data store to receive statuses published in the datastore. In some embodiments, rather than subscribing with the datarecords, the application agent periodically polls/checks the data store.In some embodiments, the status of the device is received by anapplication agent directly from a proxy agent.

At 504, an expectation associated with the received status is verified.For example, one or more rules or tests are performed to verify that thestatus is as expected, specified, and/or within a range. In someembodiments, the expectation includes one or more tests to be performedto verify that a set of requirements provided by an interaction agent(e.g., published in 204 of FIG. 2A and received in 302 of FIG. 3A) hasbeen successfully achieved. For example, the received set of networkrequirements in 202 of FIG. 2A specifies one or more tests to beperformed to verify that the set of network requirements has beensuccessfully achieved. For example, in the L3 Clos network examplediscussed throughout the specification, a test to verify that routingtables have been successfully updated and leaf switch nodes are aware ofneighbors to reflect the Clos network configuration is received alongwith the network requirements received in 202 of FIG. 2A. This test maybe published by the interaction agent along with the requirements in 204of FIG. 2A and the application agent receives the test as theexpectation for verification. In some embodiments, the expectationidentifies an acceptable range for a resource utilization indicator. Insome embodiments, the expectation identifies an error state of thereceived status.

At 506, an action, if applicable, is performed based on the verificationof the expectation. In some embodiments, no action is performed if thereceived status is as expected, specified, and/or within a range. Insome embodiments, the expectation identifies the responsive action to beperformed based on the received status. In some embodiments, performingthe action includes reporting the received status. For example, a resultof a test of the expectation and/or the received status is reported(e.g., report that a test to verify that the set of network requirementshas been successfully achieved has passed to indicate that the set ofnetwork requirements have been achieved). In some embodiments, reportingthe received status includes summarizing a plurality of receivedstatuses. Reporting the status may include providing the report/statusto an interaction agent (e.g., the interaction agent may provide thereport/status to a user). In some embodiments, reporting the statusincludes publishing/updating a data record of a system data store suchas data store 104 of FIG. 1. For example, a status identifier ispublished to a data record of the data store that is subscribed by aninteraction agent.

In some embodiments, performing the action includes configuring, moving,removing, and/or adding a device of a network and/or a process/programof a device of the network. For example, the application agent generatesinstructions (e.g., publishes device requirements to a system data storefor a proxy agent to implement on a device) to automaticallymitigate/fix an error indicated by the status (e.g., repair/replacedevice that has encountered an error). In one example, when a proxyagent provides a status update that its associated device is overloaded,the application agent may add a new device to a network to offloadprocessing and/or move a processing task of the overloaded device toanother network device. The collected status information may be providedby an application agent to an interaction agent as a report and/or arequest for action.

In some embodiments, performing the action includes allowing anotherapplication agent that is configured to perform the action to performthe action. For example, an application agent that has determined thatthe received status indicates that the action should be performedinforms another application agent (e.g., by publishing to a data storesubscribed by the second application agent) to perform the action. Insome embodiments, an interaction agent manages which application agentis to perform the action. For example, the interaction agent is informedof the status and instructs (e.g., by publishing requirements to a datastore) an application agent that is able to perform responsive action toperform the responsive action. In some embodiments, performing theresponsive action includes providing responsive requirements in responseto the status that is received in 302 of FIG. 3A. For example, theresponsive requirements are translated to device requirements that willbe provided to proxy agents to be implemented.

Although the foregoing embodiments have been described in some detailfor purposes of clarity of understanding, the invention is not limitedto the details provided. There are many alternative ways of implementingthe invention. The disclosed embodiments are illustrative and notrestrictive.

What is claimed is:
 1. A system for configuring a computer network,comprising: a memory storing constraints; and a processor coupled withthe memory and configured to process a plurality of processing stages,wherein for at least one of the plurality of processing stages, anapplication agent utilizes an input declarative requirement forconfiguring the computer network to be established with at least some ofthe constraints to determine an output declarative requirement forconfiguring the computer network to be established, the inputdeclarative requirement is to be utilized to configure a computernetwork switch in establishing the computer network, the outputdeclarative requirement is at a lower level than a level of the inputdeclarative requirement, and the input declarative requirement and theoutput declarative requirement are different declarative requirements;wherein an interaction agent is able to be utilized to specify the inputdeclarative requirement at an appropriate level for any of the pluralityof processing stages; the plurality of processing stages are utilized toat least in part automatically establish and configure the computernetwork; the input declarative requirement is received via a RESTfulAPI; and configuring the network includes configuring a L3 Clos meshnetwork.
 2. The system of claim 1, wherein the processor is configuredto select a processing stage of the plurality of processing stagescorresponding to the level of the input declarative requirement.
 3. Thesystem of claim 1, wherein for each of the plurality processing stages,a corresponding input declarative requirement is processed using one ormore corresponding constraints to determine a corresponding lower levelof output declarative requirement.
 4. The system of claim 1, wherein theoutput declarative requirement is utilized as a next input declarativerequirement for another one of the plurality of processing stages. 5.The system of claim 1, wherein the output declarative requirementincludes a declarative requirement for a specific network switch device.6. The system of claim 1, further comprising an interface configured toreceive the constraints.
 7. The system of claim 1, further comprising aninterface configured to receive the input declarative requirement from auser.
 8. The system of claim 1, wherein the output declarativerequirement includes a more specific declarative requirement than theinput declarative requirement.
 9. The system of claim 1, wherein theconstraints include an identifier of a characteristic of a device of thenetwork.
 10. The system of claim 1, wherein the constraints include anidentifier of a device of the network determined to be available. 11.The system of claim 1, wherein the constraints include a policy.
 12. Thesystem of claim 1, wherein the input declarative requirement includes anidentification of a number of servers to be connected using the networkand an identification of an oversubscription ratio.
 13. The system ofclaim 1, wherein the input declarative requirement includes a cablingmapping.
 14. The system of claim 1, wherein utilizing the inputdeclarative requirement with at least some of the constraints includesassigning a soft resource identified to be available by at least one ofthe constraints to a connection identified by the input declarativerequirement.
 15. The system of claim 1, wherein at least a portion ofthe output declarative requirement is provided to a proxy agent toconfigure a device of the network.
 16. The system of claim 1, whereinthe output declarative requirement is validated.
 17. The system of claim1, wherein the output declarative requirement is analyzed to verify thatthe output declarative requirement matches an intent of the inputdeclarative requirement.
 18. The system of claim 1, wherein theplurality of processing stages are processed in a workflow order of adirected acyclic graph.
 19. A method for configuring a computer network,comprising: storing constraints; and using a processor to process aplurality of processing stages, wherein for at least one of theplurality of processing stages, an application agent utilizes an inputdeclarative requirement for configuring the computer network to beestablished with at least some of the constraints to determine an outputdeclarative requirement for configuring the computer network to beestablished, the input declarative requirement is to be utilized toconfigure a computer network switch in establishing the computernetwork, the output declarative requirement is at a lower level than alevel of the input declarative requirement, and the input declarativerequirement and the output declarative requirement are differentdeclarative requirements; wherein an interaction agent is able to beutilized to specify the input declarative requirement at an appropriatelevel for any of the plurality of processing stages; the plurality ofprocessing stages are utilized to at least in part automaticallyestablish and configure the computer network; the input declarativerequirement is received via a RESTful API; and configuring the networkincludes configuring a L3 Clos mesh network.
 20. The method of claim 19,further comprising selecting a processing stage of the plurality ofprocessing stages corresponding to the level of the input declarativerequirement.
 21. The method of claim 19, wherein for each of theplurality processing stages, a corresponding input declarativerequirement is processed using one or more corresponding constraints todetermine a corresponding lower level of output declarative requirement.22. A computer program product for configuring a computer network, thecomputer program product being embodied in a non-transitory computerreadable storage medium and comprising computer instructions for:storing constraints; and processing a plurality of processing stages,wherein for at least one of the plurality of processing stages, anapplication agent utilizes an input declarative requirement forconfiguring the computer network to be established with at least some ofthe constraints to determine an output declarative requirement forconfiguring the computer network to be established, the inputdeclarative requirement is to be utilized to configure a computernetwork switch in establishing the computer network, the outputdeclarative requirement is at a lower level than a level of the inputdeclarative requirement, and the input declarative requirement and theoutput declarative requirement are different declarative requirements;wherein an interaction agent is able to be utilized to specify the inputdeclarative requirement at an appropriate level for any of the pluralityof processing stages; the plurality of processing stages are utilized toat least in part automatically establish and configure the computernetwork; the input declarative requirement is received via a RESTfulAPI; and configuring the network includes configuring a L3 Clos meshnetwork.